Process of ethylating amines



Patented Jan. 19, 1926.

UNITED STATES PATENT OFFICE.

ARTHUR R. CADE, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR T0 CARBIDE AND CARBON CHEMICALS CORPORATION,

A CORPORATION OF NEW YORK.

PROCESS OF ETHYLATING- AMINES.

No Drawing.

To all whom it may concern:

Be it known that I,-ARTHUR R. CADE, a ta Application filed July 17, 1923. Serial No. 652,191. I

The process is applicable to amines conining either alkyl or aryl groups or both,

citizen of the United States, residing at but will be described in connection with the Pittsburgh, in the county of Allegheny and ethvlation of aniline with diethyl sulphate.

State of Pennsylvania, have invented cer- VVh-en aniline is treated with diethyl-sultain new and useful Improvements in phate under ethylating conditions, several of which di action product and their formation may Processes of Ethylating Amines, the following is a specification.

The invention is a process of ethylatnig re iferent products are possible. Both monodiethyl aniline are usually found in the primary or secondary amines using an ethyl be illustrated by the following equations:

sulphate monoethyl ine anll sulphate The ethyl hydrogen sulphate formed as point for about five hours.

monoethyl ethyl hydrogen aniline sulphat ylh drogen aniline sulp ate The reaction above will combine with unchanged amline product may be distilled with steam, 'or

and with both the ethyl anilines to form saltshomologous with one or both the aniline sulphates (C H NH H SO, G H NH H SO This salt-forming reaction is not, properly may be and the ethyl product speaking, an ethylation,

water may be added and the mixture extracted with a suitable solvent immiscible and with water.

The proportions of the reacting materials varied somewhat, depending on the desired. To obtain alproduct free groups which are consumed in the reaction from unethylated aniline, the quantity of are lost to the ethylation process. sibility of decomposing, the salts with a stronger base than the amlne, thereby rethat required to ethylate the ani- The posdiethyl sulphate used is preferably in slight 1 excess of line completely, while for the most complete storing to the ethylation process the ethyl utilization of the ethylating capacity of the accorddi groups combined in salt formation, 1

ethyl sulphate, ied in quantity more than sufiicient to combine with all "the sulphate radicle present. For the result referred to, about. 11 mols of ethyl sulphate and 12 mols-of calcium available for ethylation of the amine, is hydroxid to 10 mols of aniline is the preconverted into ethyl alcohol, which is of ferred proportion,

course an undesired result. In accordance with my invention an alkaline-earth hydroxid or magnesium hydroxid is employed, calcium hydroxid being preferred.

To carry out the process, aniline, dlethyl sulphate, and the hydroxid are mixed tothe hydroxid should be apthough a larger excess of lime does no harm. With a sufiicient quanmetal tity of lime and other proper conditions, a large proportion of both ethyl groups of the ethylating agents are utilized.

If a product containing unchanged aniline is wanted, a smaller proportion ofdigether (the order of mixing is immaterial) ethyl sulphate may be used, while in a parand heated under a. reflux condenser,

heating being gradual to avoid too rapid a the ethyl anilines in certain proportions but reaction. The temperature is eventually free from unused aniline was desired, the

raised to about C. and held at this re sult'was obtained by using a quantity of lime insuflicient to combine with all the sulphate radicle present.

The better utilization of the ethyl groups C H NHC,H,-O,H HSO CaO H, monoethyl aniline-ethyl hydrogen cale um sulphate salt While calcium hydroxid commends itself because of its low price, the hydroxids of the other alkaline earth metals or of magnesium can also be used with good results.

I claim:

1. Process of ethylating amines which comprises treating the amine to be ethylated with an ethyl sulphate under ethylating conditions and in the presence of an alkaline compound of an alkaline-earth metal.

2. Process according to claim 1 in which the metal compound is present in quantity at least sufiicient to fix all the sulphate radicle present.

3. Process according to claim 1 in which i hydroxld when lime is used may be explained by the following equation:

= CaSO4 'l' O6H8N(G2H5)2 calcium water diethyl aniline sulphate the amine to be ethylated is aniline.

4. Process according to claim 1 in which the alkaline-earth compound used is calcium hydroxid.

5. Process of ethylating aniline which comprises treating it under ethylating conditions with diethyl sulphate, in the presence of an alkaline compound of an alkaline-earth metal.

6. Process according to claim 5 in which the alkaline-earth compound used is calcium hydroxid.

In testimony whereof, I affix my signature.

ARTHUR R. CADE. 

